Guest:Aaron Parsons (UC, Berkeley). We talked about the PAPER experiment, which is hoping to shed light on the end of the “dark ages” of the Universe, just as the first stars and galaxies started to form.

Guest: Kristen Coppin and James Geach (both post-doctoral researchers at McGill University). We interviewed Kristen and Jim to discuss their results, recently published in a press release. They discovered a large structure of packed galaxies joining two galaxy clusters. We discussed this new result and its implications.

Guest: George Helou, Executive director of the Infrared Processing and Analysis Center at CalTech, and deputy director of the Spitzer Infrared Telescope Science team. We discussed his scientific research: Space infrared astronomy and galaxies.